Don't worry about the bouncing ball test too much, or it's comments that you're not up to the standard. Almost everyone i know got the comments and retest, and still get selected. So don't get demoralised or distracted.
The tests look like a lot of work, but it's really not that tough. Personally, I think it's much more impt to be well rested the night before, and just be alert during the test itself.
Some of the tests in similar forms are available on the internet. e.g. the contact points with the blocks. So do a search and have a little practice.